g_eli_crypto.c revision 262318
1/*-
2 * Copyright (c) 2005-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/10/sys/geom/eli/g_eli_crypto.c 262318 2014-02-22 00:30:33Z delphij $");
29
30#include <sys/param.h>
31#ifdef _KERNEL
32#include <sys/systm.h>
33#include <sys/kernel.h>
34#include <sys/malloc.h>
35#include <sys/uio.h>
36#else
37#include <stdint.h>
38#include <string.h>
39#include <strings.h>
40#include <errno.h>
41#include <assert.h>
42#include <openssl/evp.h>
43#define	_OpenSSL_
44#endif
45#include <geom/eli/g_eli.h>
46
47#ifdef _KERNEL
48MALLOC_DECLARE(M_ELI);
49
50static int
51g_eli_crypto_done(struct cryptop *crp)
52{
53
54	crp->crp_opaque = (void *)crp;
55	wakeup(crp);
56	return (0);
57}
58
59static int
60g_eli_crypto_cipher(u_int algo, int enc, u_char *data, size_t datasize,
61    const u_char *key, size_t keysize)
62{
63	struct cryptoini cri;
64	struct cryptop *crp;
65	struct cryptodesc *crd;
66	struct uio *uio;
67	struct iovec *iov;
68	uint64_t sid;
69	u_char *p;
70	int error;
71
72	KASSERT(algo != CRYPTO_AES_XTS,
73	    ("%s: CRYPTO_AES_XTS unexpected here", __func__));
74
75	bzero(&cri, sizeof(cri));
76	cri.cri_alg = algo;
77	cri.cri_key = __DECONST(void *, key);
78	cri.cri_klen = keysize;
79	error = crypto_newsession(&sid, &cri, CRYPTOCAP_F_SOFTWARE);
80	if (error != 0)
81		return (error);
82	p = malloc(sizeof(*crp) + sizeof(*crd) + sizeof(*uio) + sizeof(*iov),
83	    M_ELI, M_NOWAIT | M_ZERO);
84	if (p == NULL) {
85		crypto_freesession(sid);
86		return (ENOMEM);
87	}
88	crp = (struct cryptop *)p;	p += sizeof(*crp);
89	crd = (struct cryptodesc *)p;	p += sizeof(*crd);
90	uio = (struct uio *)p;		p += sizeof(*uio);
91	iov = (struct iovec *)p;	p += sizeof(*iov);
92
93	iov->iov_len = datasize;
94	iov->iov_base = data;
95
96	uio->uio_iov = iov;
97	uio->uio_iovcnt = 1;
98	uio->uio_segflg = UIO_SYSSPACE;
99	uio->uio_resid = datasize;
100
101	crd->crd_skip = 0;
102	crd->crd_len = datasize;
103	crd->crd_flags = CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT;
104	if (enc)
105		crd->crd_flags |= CRD_F_ENCRYPT;
106	crd->crd_alg = algo;
107	crd->crd_key = __DECONST(void *, key);
108	crd->crd_klen = keysize;
109	bzero(crd->crd_iv, sizeof(crd->crd_iv));
110	crd->crd_next = NULL;
111
112	crp->crp_sid = sid;
113	crp->crp_ilen = datasize;
114	crp->crp_olen = datasize;
115	crp->crp_opaque = NULL;
116	crp->crp_callback = g_eli_crypto_done;
117	crp->crp_buf = (void *)uio;
118	crp->crp_flags = CRYPTO_F_IOV | CRYPTO_F_CBIFSYNC | CRYPTO_F_REL;
119	crp->crp_desc = crd;
120
121	error = crypto_dispatch(crp);
122	if (error == 0) {
123		while (crp->crp_opaque == NULL)
124			tsleep(crp, PRIBIO, "geli", hz / 5);
125		error = crp->crp_etype;
126	}
127
128	free(crp, M_ELI);
129	crypto_freesession(sid);
130	return (error);
131}
132#else	/* !_KERNEL */
133static int
134g_eli_crypto_cipher(u_int algo, int enc, u_char *data, size_t datasize,
135    const u_char *key, size_t keysize)
136{
137	EVP_CIPHER_CTX ctx;
138	const EVP_CIPHER *type;
139	u_char iv[keysize];
140	int outsize;
141
142	assert(algo != CRYPTO_AES_XTS);
143
144	switch (algo) {
145	case CRYPTO_NULL_CBC:
146		type = EVP_enc_null();
147		break;
148	case CRYPTO_AES_CBC:
149		switch (keysize) {
150		case 128:
151			type = EVP_aes_128_cbc();
152			break;
153		case 192:
154			type = EVP_aes_192_cbc();
155			break;
156		case 256:
157			type = EVP_aes_256_cbc();
158			break;
159		default:
160			return (EINVAL);
161		}
162		break;
163	case CRYPTO_BLF_CBC:
164		type = EVP_bf_cbc();
165		break;
166#ifndef OPENSSL_NO_CAMELLIA
167	case CRYPTO_CAMELLIA_CBC:
168		switch (keysize) {
169		case 128:
170			type = EVP_camellia_128_cbc();
171			break;
172		case 192:
173			type = EVP_camellia_192_cbc();
174			break;
175		case 256:
176			type = EVP_camellia_256_cbc();
177			break;
178		default:
179			return (EINVAL);
180		}
181		break;
182#endif
183	case CRYPTO_3DES_CBC:
184		type = EVP_des_ede3_cbc();
185		break;
186	default:
187		return (EINVAL);
188	}
189
190	EVP_CIPHER_CTX_init(&ctx);
191
192	EVP_CipherInit_ex(&ctx, type, NULL, NULL, NULL, enc);
193	EVP_CIPHER_CTX_set_key_length(&ctx, keysize / 8);
194	EVP_CIPHER_CTX_set_padding(&ctx, 0);
195	bzero(iv, sizeof(iv));
196	EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, enc);
197
198	if (EVP_CipherUpdate(&ctx, data, &outsize, data, datasize) == 0) {
199		EVP_CIPHER_CTX_cleanup(&ctx);
200		return (EINVAL);
201	}
202	assert(outsize == (int)datasize);
203
204	if (EVP_CipherFinal_ex(&ctx, data + outsize, &outsize) == 0) {
205		EVP_CIPHER_CTX_cleanup(&ctx);
206		return (EINVAL);
207	}
208	assert(outsize == 0);
209
210	EVP_CIPHER_CTX_cleanup(&ctx);
211	return (0);
212}
213#endif	/* !_KERNEL */
214
215int
216g_eli_crypto_encrypt(u_int algo, u_char *data, size_t datasize,
217    const u_char *key, size_t keysize)
218{
219
220	/* We prefer AES-CBC for metadata protection. */
221	if (algo == CRYPTO_AES_XTS)
222		algo = CRYPTO_AES_CBC;
223
224	return (g_eli_crypto_cipher(algo, 1, data, datasize, key, keysize));
225}
226
227int
228g_eli_crypto_decrypt(u_int algo, u_char *data, size_t datasize,
229    const u_char *key, size_t keysize)
230{
231
232	/* We prefer AES-CBC for metadata protection. */
233	if (algo == CRYPTO_AES_XTS)
234		algo = CRYPTO_AES_CBC;
235
236	return (g_eli_crypto_cipher(algo, 0, data, datasize, key, keysize));
237}
238
239void
240g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const uint8_t *hkey,
241    size_t hkeylen)
242{
243	u_char k_ipad[128], key[128];
244	SHA512_CTX lctx;
245	u_int i;
246
247	bzero(key, sizeof(key));
248	if (hkeylen == 0)
249		; /* do nothing */
250	else if (hkeylen <= 128)
251		bcopy(hkey, key, hkeylen);
252	else {
253		/* If key is longer than 128 bytes reset it to key = SHA512(key). */
254		SHA512_Init(&lctx);
255		SHA512_Update(&lctx, hkey, hkeylen);
256		SHA512_Final(key, &lctx);
257	}
258
259	/* XOR key with ipad and opad values. */
260	for (i = 0; i < sizeof(key); i++) {
261		k_ipad[i] = key[i] ^ 0x36;
262		ctx->k_opad[i] = key[i] ^ 0x5c;
263	}
264	bzero(key, sizeof(key));
265	/* Perform inner SHA512. */
266	SHA512_Init(&ctx->shactx);
267	SHA512_Update(&ctx->shactx, k_ipad, sizeof(k_ipad));
268	bzero(k_ipad, sizeof(k_ipad));
269}
270
271void
272g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data,
273    size_t datasize)
274{
275
276	SHA512_Update(&ctx->shactx, data, datasize);
277}
278
279void
280g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize)
281{
282	u_char digest[SHA512_MDLEN];
283	SHA512_CTX lctx;
284
285	SHA512_Final(digest, &ctx->shactx);
286	/* Perform outer SHA512. */
287	SHA512_Init(&lctx);
288	SHA512_Update(&lctx, ctx->k_opad, sizeof(ctx->k_opad));
289	bzero(ctx, sizeof(*ctx));
290	SHA512_Update(&lctx, digest, sizeof(digest));
291	SHA512_Final(digest, &lctx);
292	/* mdsize == 0 means "Give me the whole hash!" */
293	if (mdsize == 0)
294		mdsize = SHA512_MDLEN;
295	bcopy(digest, md, mdsize);
296}
297
298void
299g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize, const uint8_t *data,
300    size_t datasize, uint8_t *md, size_t mdsize)
301{
302	struct hmac_ctx ctx;
303
304	g_eli_crypto_hmac_init(&ctx, hkey, hkeysize);
305	g_eli_crypto_hmac_update(&ctx, data, datasize);
306	g_eli_crypto_hmac_final(&ctx, md, mdsize);
307}
308